Well conduit treating apparatus

ABSTRACT

An apparatus which injects successively smaller solid particles into a flowing well conduit where the injected particles are carried to a downstream restriction to form a flow interrupting plug. After the plug is formed, the apparatus injects a heavy fluid into the flow conductor to overcome the formation pressure. The injector apparatus includes a plurality of tubular chambers, each of which contains solid plugging particles of predetermined size. The ends of the chambers are equipped with valving means and a source of high pressure fluid is connected to the inlet end of each chamber. Sequential opening of the valves at the chamber ends permits the high pressure fluid in the inlet end to drive the particles from each of the chambers and inject them into the well flow conduit. After the plug is formed at the restriction, heavy fluid is pumped through a well control fluid supply line which opens into the well conduit through the injector. In a modified form, a single tubular chamber contains the graded plugging particles in sequential order according to size. A valving means at the outlet end of the chamber is employed to regulate injection of particles into the well conduit. The inlet end of the chamber is connected to a supply line which provides the fluid drive forcing the plugging materials into the flow conductor and also provides the inlet source for the heavy well treating fluid.

United States Patent Rowley 1 WELL CONDUIT TREATING APPARATUS [72] Inventor: Kermit G. Rowley,l-louston,Tex.

[73] Assignee: Tenneco Oil Company, Houston,

I Tex. 22 Filed: "Dec.l4, 1970 V 211 Appl.No.: 97,940

Related US. Application Data [63] Continuation-in-part of Ser. No. 29,091, April 16, 1970, Pat. No. 3,647,000.

Primary Examiner-Marvin A. Champion'- Assistant Examiner-Lawrence .l. Staab Attorney-Eugene S. Coddou and Carlos A. Torres [151 3,698,474 Oct. 17, 1972 [s71 1 ABSTRACT An apparatus which injects successively smaller solid particles into a flowing well conduit where the injected particles are carried to a downstream restriction to form a flow interrupting plug. After the plug is formed, the apparatus injects a heavy fluid into the flow conductor to overcome the formation (pressure. The injector apparatus includes a plurality of tubular chambers, each of which contains solid plugging particles of predetermined size. The ends of the chambers are equipped with valving means and a source of high pressure fluid is connected to the inlet end of each chamber. Sequential opening of the valves at the chamber ends permits the high pressure fluid in the inlet end to drive the particles from each of the chambers and inject them into the well flow conduit. After the plug is formed at the restrictiom heavy fluid is pumped through a well control fluid supply line which opens into the well conduit through the injector.

In a modified form, a single tubular chamber contains the graded plugging particles in sequential order ac- V cording to size. A valving means at the outlet end of 13 Claims, 4 Drawing Figures WELL CONDUIT TREATING APPARATUS A CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of U. S. Pat.'Application Ser. No. 29,091 entitled Method for Controlling Well Blowouts, filed Apr. 16, 1970, now

US. Pat. No. 3,647,000.

BACKGROUND OF THE INVENTION inoperative. When this happens, pressurized fluids in the formation penetrated by the well conduit may flow uncontrollably through the conduit in what is commonly referred to as a blowout. Where automatic equipment disposed downhole in the well conduit fails to operate properly, the well effluent may be spilled onto the waters surface causing pollution of the natural environment. The combustibility of the well effluents creates substantial danger from fire or explosion and may prevent or hamper efforts designed to bring the flow under control.

Various conventional methods have been employed to bring the well under control following a blowout. One such method requires that any fire be extinguished and that a cap be secured over the ruptured well conduit. The danger from fire and explosion in this method is apparent. Another prior art technique includes forming annular plugs of concrete in the well structure below the point of rupture and U-tubing a heavy well control fluid (mud) down into the central flow conductor of the well structure to stop the effluent flow and to 2 SUMMARY OF THE INVENTION A material injector device is connected into a well flow conduit at a point which is upstream of a restriction in the conduit. The injector includes a plurality of chambers which hold graded sizes of solid plugging material (lost circulation material) between inlet and outlet valving means. The outlet ends of each of the chambers converge to a single line which in turn connects into an inlet pipe connected into the well flow conduit. The upstream ends of the material containing chambers connect to a line which carries. a high pressure driving fluid. When the upstream and downstream valves on any chamber are opened, the high pressure fluid overcomes the well pressure and drives the solid plugging materials through the injectorand into the well flow conduit where the effluent flow through the conduit carries the plugging materials to the restriction.

extinguish any surface fires. Other techniques have in- I cluded the use of in-place equipment capable of being activated below the well head to terminate the blowout. Still another suggested technique includes the formation of dual hot taps with the lower tap serving as a bypass to effluent flow while the upper tap is employed to form a plug between two crimped portions in the flow conductor. After formation of the plug, a heavy mud is injected into the lower bypass line to kill the well.

In the previously referred to parent case entitled Method for Controlling Well Blowouts assigned to the present Assignee, an improved method for control of a well blowout is described in detail. In the parent case, the described method includes the steps of injecting a solid plugging material into a flowing well conduit at a point which is upstream from a restriction in the conduit to cause a plug to form internally of the conduit in the area of the restriction. This terminates, or substantially terminates, the effluent flow past the restriction and the hot tap thereafter serves as the point of introduction of heavy mud which kills the well. The present invention relates to apparatus employed in forming the plug and injecting the heavy mud during the practice of the method of the parent application.

At the point of restriction, the plugging particles accumulate and form a plug which retards or interrupts the flow of well effluent. The largest particles are released into the well flow conduit first, and then succeedingly smaller particles contained in different chambers of the material injector are released to form a substantially solid plug, which may severely retard or completely terminate effluent flow. After the plug has formed, a well control fluid supply means is opened to permit a heavy, non-combustible well fluid or mud to be injected into the well until the weight of the mud injected into the well flow conduit overcomes the formation pressure thereby killing the well.

In a modified form, a single chamber is employed for containing the graded particle sizes. A valving means at one end of the chamber regulates: the introduction of particles into the well flow conduit, and a single line at the upstream end of the chamber provides both the driving fluid which forces the particles into the well flow conduit, and the killing fluid which is employed to overcome the formation pressure.

Other features and advantages of the present invention will become more readily apparent form the following specification, the related drawings and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial vertical elevation illustrating the well conduit treating apparatus of the present invention as employed in an oil or gas well located in a body of water;

FIG. 2 is a partial vertical elevation, partially in section illustrating the material injector means of the present invention;

FIG. 3 is a partial vertical section, partially broken away, illustrating a single chamber and material regulating valve means in the material storage portion of the injector of the present invention; and

FIG. 4 is a partial vertical elevation, partially in section, illustrating a modified form of the well conduit treating apparatus of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to FIG. 1, the well conduit treating apparatus of the present invention is indicated generally at 10. The apparatus 10 includes a material injector section indicated generally at 11, connected into a well flow conduit W. The well flow conduit W is illustrated extending vertically through a body of water B. In the illustration of FIG. 1, only the well flow conduit W is illustrated and the conventional well structure such as casing which is normally employed in oil and gas wells has been omitted for purposes of clarity.

The injector section 11 is connected into the well conduit W through an appropriate fitting T which may be a hot tap or other suitable connection. A crimp C is formed in the well conduit W downstream from the point where the injector 11 taps into the well conduit. As will be understood, the apparatus is employed where there is uncontrolled flow of well effluents from the conduit W at a point which is downstream from the crimp C. In the embodiment of FIG. 1, the direction of effluent flow through the conduit W is from the bottom to the top.

The material injector section 11 includes a plurality of tubular material containing chambers 12, 13 and 14. The chambers include fluid regulating valves 12a, 13a and 14a at their inputs and material regulating valves 12b, 13b and 14b at their outputs. The valves may be conventional plug valves or other suitable means.

The fluid regulating valves at the input of the material storage chambers regulate the flow of a high pressure driving fluid supplied through a driving fluid supply line 15. The supply line 15 may extend to the surface of the water body B where it is connected to a source of high pressure liquids or gas (not shown). The line 15 is connected into the various fluid regulating valves of the material storage chambers by suitable fittings F.

Referring to FIG. 2, it may be seen that the outlet ends of the material storage chambers 12, 13 and 14 are connected into a plural input fitting 16 which is provided with internal passages which converge into a single output line 17. The line 17 is connected to a conduit inlet 18 by means of conventional fittings F. A fluid supply line 19 connects into the injector 11 through a fitting F". It will be understood that the line 19 extends to the surface where it is connected with a source (not shown) of high pressure fluid of controllable density.

As best shown by joint reference to FIGS. 2 and 3, the chambers, 12, 13 and 14 include graded sizes of plugging material particles P,,, P,, and P The particles P range in size from the largest, P shown in the chamber 12 to the smallest, P shown in chamber 14. The material of particles P P and P may be any substance which can withstand the high pressures encountered in the conduit W. The individual particles P should have external dimensions which are greater than the internal dimensions of the crimp C so that they will lodge at the crimp. The particles P should preferably be smaller than particles P and particles P should be smaller than particles P so that the particles form a substantially complete plug.

In the operation of the well conduit treating apparatus 10, the well conduit W is preferably tapped by means of the hot tap T or other suitable means whereby the injector portion 11 may be secured by an inlet conduit to the internal portions of the well flow conduit W. When properly attached to the conduit, a high fluid pressure such as may be provided by compressed nitrogen or other suitable liquid or gas is supplied to the injector through the line 15. It will be understood that the pressure of the gas in line 15 must be greater than the pressure existing within the well conduit W to effect the desired material flow into the conduit.

The well control method involved with the present invention requires the presence of a restriction downstream of the tap-in of the material injector. Such a flow restriction may be provided by forming a crimp or restriction such as the crimp C in the well conduit or may be provided by any other suitable means. Once the injector has been secured to the tap-in point, the material regulating valve 12b and the fluid regulating valve 12a of the chamber 12 are opened. As illustrated in FIG. 3, the pressure of the fluid in line 15 drives the plugging material P through the chamber 12 toward the conduit inlet means 18.

When the particles P have entered the well conduit W, the flow of well effluents carries the particles upwardly where they lodge in the flow restriction C. After the particles P have been evacuated from the chamber 12, the valve 12 for the chamber is closed and the material regulating valve 13b and flow regulating valve 13a in the chamber 13 are then opened to force the plugging material particles P into the conduit W where they are carried to the flow restriction C causing them to lodge against the previously lodged particles P,,. The valves at either end of the chamber 13 are then closed, and the valves 14a and 14b in the chamber 14 are opened to force the particles p in the chamber 14 into the conduit C. small particles P The relatively small particles P are carried up into the plug formed internally of the well conduit at the restriction C where they tend to further restrict flow through the plug. The valves 14a and 14b are then closed.

Following formation of the plug in the well conduit W, a heavy well treating fluid or mud is injected into the well conduit C through the line 19. The heavy fluid or mud flows downwardly through the conduit under the influence of the pressure in the line 19 until the weight of the fluid is sufficient to overcome the formation pressure. At this point, the well is killed and may be completely closed in by any suitable means.

The material regulating valves may be simple,

manually operated plug valves as illustrated in FIG. 3

or may be any other suitable means. When the valve is in open position, the solid plugging particles P are free to move through the opening in the valve closure member into the well conduit W. When the valves are in closed position, a pressure-tight seal is provided.

A modified form of the invention, indicated generally at 110, is illustrated in FIG. 4 of the drawings. The modified form of the invention includes a single chamber 111 within which the particles P,,, P and P,. are contained. If desired, wadding S or other suitable means may be employed to maintain the plugging material particles separate from each other according to size. A single supply line 115 extends from the injector l10 to the surface or other supply source. The inlet end of the material storage chamber 111 is equipped with a valve 111a and the outlet end is equipped with a valve lllb.

In the operation of the apparatus 110, the valves 111a and lllb are opened to permit a source of high pressure gas or liquid in the line 115 to drive the particles P P and P sequentially into the well conduit W where they provide the desired plug at the constriction C. After the plug has been formed, thefluid employed to kill the well may then be injected through the same line 115.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof, and various changes in the size, shape and materials as well as in the details of the illustrated construction may be made within the scope of the appended claims without departing from the spirit of the invention.

What is claimed is:

1. Well conduit treating apparatus comprising:

a. well flow conduit means; i

b. conduit inlet means opening into said well flow conduit means;

c. flow restrictive means disposed in said well flow conduit means downstream of said conduit inlet means for restricting the flow of well fluids through said well flow conduit means;

d. material injector means connected with said conduit inlet means for injecting plugging material into said well flow conduit means whereby fluid flow through said well flow conduit meanscarries said plugging material to said restriction to form a flow interrupting plug at said restriction;

e. material storage means for containing said plugging material;

f. storage outlet means extending between said storage means and said conduit inlet means for conveying said plugging material from said storage outlet means to said conduit inlet means; and

g. a plurality of particles of solid plugging material having graded sizes and located in said material injector means.

2. A well conduit treating apparatus as defined in claim 1 further including flow control means included in said storage outlet means for preventing flow through said storage outlet means.

3. A well conduit treating apparatus as defined in claim 1 further including regulating means for selectively permitting insertion of said plugging material particles of a predetermined size into said well flow conduit means.

4. Well conduit treating apparatus comprising:

a. well flow conduit means;

b. conduit inlet means opening into said well flow conduit means;

c. flow restrictive means disposed in said well flow conduit means downstream of said conduit inlet means for restricting the flow of well fluids through said well flow conduit means;

d. material injector means connected with said conduit inlet means for injecting plugging material into said well flow conduit means whereby fluid flow through said well flow conduit means carries said plugging material to said restriction to form a flow interrupting plug at said restriction;

e. material storage means for containing said plugging material;

f. storage outlet means extending between said storage means and said conduit inlet means for conveying said plugging material from said storage outlet means to said conduit inlet means; and

g. driving fluid supply means extending into said storage means for supplying a relatively high pressure driving fluidto said storage means for driving said plugging material from said storage means into said well flow conduit means.

5. A well conduit treating apparatus as defined in claim 4 wherein said material storage means includes a plurality of containing portions for containing solid plugging materials.

6. A well conduit treating apparatus as defined in claim 5 wherein each of said plurality of containing portions includes; I

a. chamber means with a material regulating valve means at its output end for selectively permitting injection of plugging material contained in said chamber means into said well flow conduit means;

. and t r b. fluid regulating valve means at its input end for regulating the flow of said high pressure driving fluid into said chamber means.

7. A well conduit treating apparatus as defined in claim 9 further including well control fluid supply means connected to said conduit inlet means for inserting a relatively heavy well control fluid into said well flow conduit means after said flow interrupting plug is formed.

8. Well conduit treating apparatus comprising:

a. well flow conduit means;

b. conduit inlet means opening into said well flow conduit means;

c. flow restrictive means disposed in said well flow conduit means downstream of said conduit inlet means for restricting 'the flow of well fluids through said well flow conduit. means;

(1. material injector means connected with said conduit inlet means for injecting plugging material into said well flow conduit means whereby fluid flow through said well flow conduit means carries said plugging material to said restriction to form a flow interrupting plug at said restriction;

e. material storage means for containing said plugging material;

f. storage outlet means extending between said storage means and said conduit inlet means for conveying said plugging material from said storage outlet means to said conduit inlet means; and

g. means for injecting well treating fluid into said well flow conduit means.

9. A well conduit treating apparatus comprising:

a. material injector means for injecting well control fluids and solid plugging particles into a well conduit;

b. a plurality of material storage chambers included in said injector means for containing graded plugging particles;

c. regulating means included with said chambers for selective control of the flow of the particles from each of said chambers into said well conduit;

(1. driving fluid supply means connected with said chambers for supplying a relatively high pressure driving fluid to said chambers for driving the plugging particles from their containing chambers into said well conduit; and

e. a tubular housing included in each of said cham- I bers, said housing having inlet and outlet ends and having valve means at each of said ends with said valve means at said outlet ends of each of said chambers converging to a plural input fitting having a single output flow path and said valve means at said inlet ends of each of said chambers connectin g to said driving fluid supply means. 10. A well conduit treating apparatus as defined in claim 9 further including well control fluid supply means connected into said output flow path of said plural input fitting for supplying a relatively heavy well control fluid into said well flow conduit means.

11. A well conduit treating apparatus as defined in claim 10 further including:

a. a well flow conduit means connected with said material injector means; and

b. flow restrictive means disposed insaid well flow conduit means downstream from the connection with said injector means for restricting the flow of well fluids through said well flow conduit means whereby fluid flow through said well flow conduit means carries said plugging materials to said restriction to form a flow interrupting plug at said restriction.

12. A well conduit treating apparatus comprising:

a. material injector means for injecting well control fluids and solid plugging particles into a well conduit;

b. a plurality of material storage chambers included in said injector means for containing graded plugging particles;

c. regulating means included with said chambers for selective control of the flow of the particles from each of said chambers into said well conduit;

cl. a well flow conduit means connected with said material injector means; and

e. flow restrictive means disposed in said well flow conduit means downstream from the connection 'with said injector means for restricting the flow of well fluids through said well flow conduit means whereby'fluid flow through said well flow conduit means carries said plugging materials to said restriction to form a flow interrupting plug at said restriction. r

13. A well conduit treating apparatus comprising:

a. material injector means for injecting well control fluids and solid plugging particles into a well conduit;

b. a plurality of material storage chambers included in said injector means for containing graded plugging particles;

0. regulating means included with said chambers for selective control of the flow of the particles from each of said chambers into said well conduit; I

d. driving fluid supply means connected with said chambers for supplying a relatively high pressure driving fluid to said chambers for driving plugging particles from their respective containing chambers into said well conduit;

e. a well flow conduit means connected with said material injector means; and

f. flow restrictive means disposed in said well flow conduit means downstream from the connection with said injector means for restricting the flow of well fluids through said well flow conduit means whereby fluid flow through said well flow conduit means carries said plugging materials to said restriction to form a flow interrupting plug at said 

1. Well conduit treating apparatus comprising: a. well flow conduit means; b. conduit inlet means opening into said well flow conduit means; c. flow restrictive means disposed in said well flow conduit means downstream of said conduit inlet means for restricting the flow of well fluids through said well flow conduit means; d. material injector means connected with said conduit inlet means for injecting plugging material into said well flow conduit means whereby fluid flow through said well flow conduit means carries said plugging material to said restriction to form a flow interrupting plug at said restriction; e. material storage means for containing said plugging material; f. storage outlet means extending between said storage means and said conduit inlet means for conveying said plugging material from said storage outlet means to said conduit inlet means; and g. a plurality of particles of solid plugging material having graded sizes and located in said material injector means.
 2. A well conduit treating apparatus as defined in claim 1 further including flow control means included in said storage outlet means for preventing flow through said storage outlet means.
 3. A well conduit treating apparatus as defined in claim 1 further including regulating means for selectively permitting insertion of said plugging material particles of a predetermined size into said well flow conduit means.
 4. Well conduit treating apparatus comprising: a. well flow conduit means; b. conduit inlet means opening into said well flow conduit means; c. flow restrictive means disposed in said well flow conduit means downstream of said conduit inlet means for restricting the flow of well fluids through said well flow conduit means; d. material injector means connected with said conduit inlet means for injecting plugging material into said well flow conduit means whereby fluid flow through said well flow conduit means carries said plugging material to said restriction to form a flow interrupting plug at said restriction; e. material storage means for containing said plugging material; f. storage outlet means extending between said storage means and said conduit inlet means for conveying said plugging material from said storage outlet means to said conduit inlet means; and g. driving fluid supply means extending into said storage means for supplying a relatively high pressure driving fluid to said storage means for driving said plugging material from said storage means into said well flow conduit means.
 5. A well conduit treating apparatus as defined in claim 4 wherein said material storage means includes a plurality of containing portions for containing solid plugging materials.
 6. A well conduit treating apparatus as defined in claim 5 wherein each of said plurality of containing portions includes: a. chamber means with a material regulating valve means at its output end for selectively permitting injection of plugging material contained in said chamber means into said well flow conduit means; and b. fluid regulating valve means at its input end for regulating the flow of said high pressure driving fluid into said chamber means.
 7. A well conduit treating apparatus as defined in claim 9 further including well control fluid supply means connected to said conduit inlet means for inserting a relatively heavy well control fluid into said well flow conduit means after said flow interrupting plug is formed.
 8. Well conduit treating apparatus comprising: a. well flow conduit means; b. conduit inlet means opening into said well flow conduit means; c. flow restrictive means disposed in said well flow conduit means downstream of said conduit inlet means for restricting the flow of well fluids through said well flow conduit means; d. material injector means connecteD with said conduit inlet means for injecting plugging material into said well flow conduit means whereby fluid flow through said well flow conduit means carries said plugging material to said restriction to form a flow interrupting plug at said restriction; e. material storage means for containing said plugging material; f. storage outlet means extending between said storage means and said conduit inlet means for conveying said plugging material from said storage outlet means to said conduit inlet means; and g. means for injecting well treating fluid into said well flow conduit means.
 9. A well conduit treating apparatus comprising: a. material injector means for injecting well control fluids and solid plugging particles into a well conduit; b. a plurality of material storage chambers included in said injector means for containing graded plugging particles; c. regulating means included with said chambers for selective control of the flow of the particles from each of said chambers into said well conduit; d. driving fluid supply means connected with said chambers for supplying a relatively high pressure driving fluid to said chambers for driving the plugging particles from their containing chambers into said well conduit; and e. a tubular housing included in each of said chambers, said housing having inlet and outlet ends and having valve means at each of said ends with said valve means at said outlet ends of each of said chambers converging to a plural input fitting having a single output flow path and said valve means at said inlet ends of each of said chambers connecting to said driving fluid supply means.
 10. A well conduit treating apparatus as defined in claim 9 further including well control fluid supply means connected into said output flow path of said plural input fitting for supplying a relatively heavy well control fluid into said well flow conduit means.
 11. A well conduit treating apparatus as defined in claim 10 further including: a. a well flow conduit means connected with said material injector means; and b. flow restrictive means disposed in said well flow conduit means downstream from the connection with said injector means for restricting the flow of well fluids through said well flow conduit means whereby fluid flow through said well flow conduit means carries said plugging materials to said restriction to form a flow interrupting plug at said restriction.
 12. A well conduit treating apparatus comprising: a. material injector means for injecting well control fluids and solid plugging particles into a well conduit; b. a plurality of material storage chambers included in said injector means for containing graded plugging particles; c. regulating means included with said chambers for selective control of the flow of the particles from each of said chambers into said well conduit; d. a well flow conduit means connected with said material injector means; and e. flow restrictive means disposed in said well flow conduit means downstream from the connection with said injector means for restricting the flow of well fluids through said well flow conduit means whereby fluid flow through said well flow conduit means carries said plugging materials to said restriction to form a flow interrupting plug at said restriction.
 13. A well conduit treating apparatus comprising: a. material injector means for injecting well control fluids and solid plugging particles into a well conduit; b. a plurality of material storage chambers included in said injector means for containing graded plugging particles; c. regulating means included with said chambers for selective control of the flow of the particles from each of said chambers into said well conduit; d. driving fluid supply means connected with said chambers for supplying a relatively high pressure driving fluid to said chambers for driving plugging particles from their respective containing chambers into said well conduit; e. a well flow conduit means connected with said material injector means; and f. flow restrictive means disposed in said well flow conduit means downstream from the connection with said injector means for restricting the flow of well fluids through said well flow conduit means whereby fluid flow through said well flow conduit means carries said plugging materials to said restriction to form a flow interrupting plug at said restriction. 